Flexible Footwear With Puncture Resistant Sole And Reinforced Strap Mounting

ABSTRACT

A flexible article of footwear, such as a sandal or the like, with a puncture resistant sole and reinforced strap mount. The article of footwear can also have an adjustable forefoot strap, and the sole can have a midsole, outsole and puncture resistant plate that can be integrally molded together. In some embodiments, the insole can be contoured to match the contour of the wearer&#39;s foot compete with arch support.

CROSS-REFERENCE To RELATED APPLICATION

This application claims priority to U.S. provisional patent application Ser. No. 61/833,917 filed on Jun. 11, 2013, the disclosure of which is hereby incorporated by reference.

BACKGROUND

Articles of footwear generally include two primary elements, an upper and a sole structure. The upper is formed from a variety of material elements (e.g., textiles, foam, leather, and synthetic leather) that are stitched or adhesively bonded together to form a void on the interior of the footwear for comfortably and securely receiving a foot. An ankle opening through the material elements provides access to the void, thereby facilitating entry and removal of the foot from the void. Alternatively, the upper can include a forefoot strap that is held in place with a toe stay or can include one or more straps that encircle the wearer's foot, footwear having these strap structures are collectively referred to herein as sandals.

The sole structure is located adjacent to a lower portion of the upper and is generally positioned between the foot and the ground. In many articles of footwear, the sole structure generally incorporates an insole, a midsole, and an outsole. The insole, which may be located within the void and adjacent to a lower surface of the void, is a thin compressible member that enhances footwear comfort. The midsole, which may be secured to a lower surface of the upper and extends downward from the upper, forms a middle layer of the sole structure. In addition to attenuating ground reaction forces (i.e., providing cushioning for the foot), the midsole may limit foot motions or impart stability, for example. The outsole, which may be secured to a lower surface of the midsole, forms the ground-contacting portion of the footwear and is usually fashioned from a durable and wear-resistant material that includes texturing to improve traction.

Generally, the midsole is the primary source of cushioning for the article of footwear, and it is primarily formed from a foamed polymer material, such as polyurethane or ethylvinylacetate, that extends throughout a length and width of the footwear. Midsoles tend to optimize support and cushioning comfort for a wearer when walking or running. Midsoles are designed to return predictable and consistent cushioning comfort and support when encountering these forces. Exemplar midsoles and uppers are shown in U.S. Patent Application Publication No. US2005/0267775A1, the disclosure of which is hereby incorporated by reference.

Sandals are often used in sandy and wet environments such as at a beach or the like. They need to protect the wearer's feet while remaining flexible and securely in place while still remaining easy to put on and remove. Exemplar sandal structures are shown in U.S. Pat. No. 7,284,341 and U.S. Patent Application Publication Nos. US2009/0313854A1 and US2012/0060390A1, all of the disclosures of which are hereby incorporated by reference.

SUMMARY

Despite the benefits of the known articles of footwear, there remains a need for a flexible article of footwear, such as a sandal or the like, that has an impact resistant sole. The article of footwear can also have an adjustable forefoot strap, and the sole can be integrally molded. In some embodiments, the insole can be contoured to match the contour of the wearer's foot complete with arch support. Also, there remains a need for reinforcing the connection of securing straps to the sole in a more durable fashion. The present invention fulfills one or more of these needs depending on the features selected from the disclosed embodiments.

Disclosed embodiments include an article of footwear having an upper and a sole structure secured to the upper, the sole structure having an insole with an outsole secured thereto, with or without a midsole therebetween, and a flexible, puncture resistant plate operably secured thereto. A securing strap extends through an opening in the insole and is operably secured to the underside of the insole. The insole is then operably secured to the plate thereby reinforcing the attachment of the strap to the sole.

In alternative embodiments, cut-outs in the midsole may be provided to match the distal ends of the straps secured thereto, thereby keeping the upper foot engaging surface substantially smooth and level without the distal ends producing a bump that can be felt by the wearer.

The advantages and features of novelty characterizing aspects of the invention are pointed out with particularity in the appended claims. To gain an improved understanding of the advantages and features of novelty, however, reference may be made to the following descriptive matter and accompanying figures that describe and illustrate various configurations and concepts related to the invention.

FIGURE DESCRIPTIONS

The foregoing Summary and the following Detailed Description will be better understood when read in conjunction with the accompanying figures.

FIG. 1 is a medial side isometric view of an article of footwear in accordance with an embodiment of the present invention.

FIG. 2 is a top, plan view of the article of footwear of FIG. 1.

FIG. 3 is a medial, side view of the article of footwear of FIG. 1.

FIG. 4 is a lateral, side view of the article of footwear of FIG. 1.

FIG. 5 is a rear, plan view of the article of footwear of FIG. 1.

FIG. 6 is a front, plan view of the article of footwear of FIG. 1.

FIG. 7 is a bottom plan view of the article of footwear of FIG. 1.

FIG. 8 is a cross-sectional view of the article of footwear taken along line 8-8 of FIG. 1.

DETAILED DESCRIPTION

The following discussion and accompanying figures disclose various configurations of foam midsoles. Concepts associated with the midsole may be applied to a wide range of footwear styles, including sandals, athletic shoes, hiking shoes and boots, ski and snowboarding boots, water shoes, and the like. Concepts associated with the midsole may also be used with footwear styles that are generally considered to be non-athletic, including dress shoes, loafers, and sandals.

An article of footwear with an impact resistant sole, an adjustable forefoot strap, a reinforced strap mount, and a method of making the same is shown in FIGS. 1-8 and described below.

General Footwear Structure

An article of footwear 10 is depicted in FIGS. 1-7, as including an upper 20 and a sole structure 30. For reference purposes, footwear 10 may be divided into three general regions: a forefoot region 11, a midfoot region 12, and a heel region 13, as shown in FIGS. 1. Footwear 10 also includes a lateral side 14 and a medial side 15. Forefoot region 11 generally includes portions of footwear 10 corresponding with the toes and the joints connecting the metatarsals with the phalanges. Midfoot region 12 generally includes portions of footwear 10 corresponding with the arch area of the foot. Heel region 13 generally includes portions of footwear 10 corresponding with rear portions of the foot, including the calcaneus bone. Lateral side 14 and medial side 15 extend through each of regions 11-13 and correspond with opposite sides of footwear 10. Regions 11-13 and sides 14-15 are not intended to demarcate precise areas of footwear 10. Rather, regions 11- 13 and sides 14-15 are intended to represent general areas of footwear 10 to aid in the following discussion. In addition to footwear 10, regions 11-13 and sides 14-15 may also be discussed with respect to the individual elements thereof, such as upper 20 and sole structure 30, and to the foot itself.

Upper 20 is depicted as having a substantially conventional configuration incorporating a variety of material elements (e.g., textile, foam, leather, and synthetic leather) that are stitched or adhesively bonded together to form an interior void for securely and comfortably receiving a foot. The material elements may be selected and located with respect to upper 20 in order to selectively impart properties of durability, air-permeability, wear-resistance, flexibility, and comfort, for example. Given that various aspects of the present application primarily relate to sole structure 30, upper 20 may exhibit the general configuration discussed above or the general configuration of practically any other conventional or nonconventional upper. Accordingly, the overall structure of upper 20 may vary significantly.

Sole structure 30 is secured to upper 20 and has a configuration that extends between upper 20 and the ground. In effect, therefore, sole structure 30 is located to extend between the foot and the ground. In addition to attenuating ground reaction forces (i.e., providing cushioning for the foot), sole structure 30 may provide traction, impart stability, and limit various foot motions, such as pronation.

Sole Configuration

Referring to FIGS. 2-7, the primary elements of sole structure 30 are an insole 29, a midsole 31, a flexible, puncture resistant plate 33, and an outsole 32. In addition, midsole 31 may incorporate one or more additional footwear elements that enhance the comfort, performance, or ground reaction force attenuation properties of footwear 10, including a polymer foam material, such as polyurethane or ethylvinylacetate, plates, moderators, lasting elements, or motion control members.

The flexible, puncture resistant plate may be sized and shaped to extend along the entire substantially horizontal surface area of the sole thereby allowing the insole to remain resistant to punctures from below the plate. The plate maybe molded and include protrusions that define recesses for receiving and holding different midsole and outsole elements thereby defining flex grooves 100 in the midsole and outsole. The flex grooves 100 may extend laterally-to-medially to allow flexibility as the wearer walks. In addition, flex grooves may extend longitudinally along the length of the sole and spaced apart from the longitudinal centerline of the sole thereby increasing torsional flexibility of the sole to accommodate the natural pronation of the wearer's foot.

Outsole 32, which may be absent in some configurations of footwear 10, is secured to a lower surface of midsole 31 and may be formed from a rubber material that provides a durable and wear-resistant surface for engaging the ground. In addition, outsole 32 may also be textured to enhance the traction (i.e., friction) properties between footwear 10 and the ground.

The insole 29 or sockliner that is located above the midsole 31 and adjacent (i.e., located nearby or close to, although not necessarily in contact with) a plantar surface or lower surface of the foot to enhance the comfort of footwear 10. The insole can be contoured to match the contours of the wearer's foot including having an arch support. More preferably, the insole is formed of a slip resistant material and includes a plurality of raised slip-resistant ridges.

A sole 30 having these basic properties may be integrally formed with conventional molding technologies such a compression molding or the like. Or one or more elements of the sole may be formed separately and joined together with the other elements of the sole with conventional techniques such as gluing, heat bonding or the like.

Adjustable Upper Construction

As best shown in FIGS. 1-4, an upper forming the article of footwear into a sandal is shown. The sandal has a forefoot strap 102 that is adjustable on the wearer's foot. The forefoot strap extends medially to laterally from the insole to define an opening for receiving a wearer's forefoot therein. A toe stay 104 extends from the sole to operably engage and support the forefoot strap 102.

A rigid clip 110 having openings 112 is secured to the distal end of the toe stay. Straps 120, 122 extend from the medial and lateral side of the forefoot strap, through respective openings in the clip 110 and fold upon themselves. A fastener 130, such as hook and loop material or the like, detachably hold each strap in a desired location, thereby allowing a wearer to adjust the fit of the strap with their foot positioned in the forefoot strap.

Reinforced Strap Attachment

Referring to FIG. 8, a reinforced strap attachment structure 200 is shown. A toe stay 104 strap extends through an opening 202 in the forefoot portion of the insole 29. Preferably the hole 202 is reinforced with a flexible grommet 204 or the like. The distal ends 206 of the toe stay 104 strap are durably secured to the underside 210 of the insole 29. Exemplar structures for rigidly securing the toe stay 104 straps to the underside of the midsole include gluing, heat sealing, and the like.

The underside 210 of the insole 29 is then durably secured to the upper surface 130 of the plate 33, thereby securing the distal ends 206 of the straps to the plate 33 and providing for a durable and reinforced attachment of the strap to the plate 33. Such attachment prevents the less tear resistant insole 29 from tearing over time due to stresses placed on the toe stay 104 during use. Exemplar structures for rigidly securing the midsole to the plate include gluing, heat sealing and the like.

The forefoot strap may be secured the plate in the same way. The distal ends of the strap are secured to the underside of the midsole, and the underside of the midsole is then durably secured to the plate.

If desired, a spacer 240 of resilient material may be secured to the underside of the insole 29 with a thickness that is approximately the thickness of the straps secured to the insole. The spacer has openings positioned where the strap engages the underside of the midsole. The spacer provide a substantially flat or smoothly countered surface so that no bumps are formed on the upper surface of the midsole by the distal ends of the straps, thereby preventing a wear from feeling the straps secured to the insole.

The invention is disclosed above and in the accompanying figures with reference to a variety of configurations. The purpose served by the disclosure, however, is to provide an example of various features and concepts related to the invention, not to limit the scope of the invention. One skilled in the relevant art will recognize that numerous variations and modifications may be made to the configurations described above without departing from the scope of the present invention, as defined by the appended claims. 

1. An article of footwear having: an upper; a sole structure operably secured to the upper, the sole structure comprising an insole, and an outsole defining a ground engaging portion; and, a flexible, puncture resistant plate operably secured to the sole between the insole and the outsole, the plate substantially covering the ground engaging portion..
 2. The article of footwear of claim 1, wherein the upper includes a forefoot strap operably secured to the sole thereby defining a sandal.
 3. The article of footwear of claim 2, further including an adjustment structure operably secured to the forefoot strap for adjusting the fit of the forefoot strap on a wearer's foot.
 4. The article of footwear of claim 1, further including a flex groove extending into the outsole.
 5. The article of footwear of claim 1, further including an midsole operably secured to the sole between the plate and the outsole.
 6. The article of footwear of claim 1, wherein said forefoot strap includes a toe stay, and said insole includes a hole for receiving the toe stay therethrough.
 7. The article of footwear of claim 6, wherein the insole has a bottom surface and the toe stay has a distal end secured to the bottom surface of the insole.
 8. The article of footwear of claim 7, further including a grommet encircling the hole for receiving the toe stay therethrough.
 9. The article of footwear of claim 7, where the bottom surface of the insole is bonded to an upper surface of the plate thereby reinforcing the toe stay.
 10. The article of footwear of claim 1, wherein the plate is contoured to conform to the shape of a wearer's foot.
 11. The article of footwear of claim 10, wherein the plate defines an arch support.
 12. The article of footwear of claim 1, further including a spacer operably secured between the bottom of the insole and the top of the plate, the spacer having substantially the same thickness of the distal end of the toe stay.
 13. The article of footwear of claim 1, wherein the spacer includes openings for receiving the distal end of the toe stay therein.
 14. The article of footwear of claim 13, wherein the openings are integrally molded with the spacer. 